Segment Information Revenues By Region (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Revenues from External Customers [Line Items]
Revenue, Net		$ 486,747	$ 506,859	$ 1,467,421	$ 1,517,473
United States and Canada [Member]
Revenues from External Customers [Line Items]
Revenue, Net		259,796	297,116	824,630	837,468
Europe, Middle East, and Africa [Member]
Revenues from External Customers [Line Items]
Revenue, Net		171,924	161,959	493,505	545,517
Other [Member]
Revenues from External Customers [Line Items]
Revenue, Net	[1]	$ 55,027	$ 47,784	$ 149,286	$ 134,488

[1] The Other region includes our operations in Latin America and Asia Pacific.